Resistance to chemotherapy is a major problem for cancer patients, especially those with advanced or metastatic disease. University of Cincinnati in USA conducted a study that revealed that exposure to bisphenol A (BPA) may reduce the effectiveness of chemotherapy treatments. The study says that BPA actually induces a group of proteins that protect cancer cells from the toxic effects of chemotherapy.
Researchers have suspected that BPA could play a role in cancer because of the chemical's structural similarities to a cancer-promoting compound called diethylstilbestrol (DES). But Ben-Jonathan's team found that BPA isn't exactly mimicking the action of DES. BPA does not increase cancer cell proliferation like DES. It is actually acting by protecting existing cancer cells from dying in response to anti-cancer drugs, making chemotherapy significantly less effective.
The team studied human breast cancer cells, subjecting them to low levels of BPA consistent with levels found in the blood of human adults. It was found that BPA is acting in cancer cells similar to the way estrogen does�by inducing proteins that protect the cells from chemotherapy agents. Estrogen's protein-inducing action has been previously linked to chemotherapy resistance, but researchers have been unable to explain why such resistance still occurs in certain patients with less estrogen. Patients with less circulating estrogen�post-menopausal women can also suffer from chemotherapy resistance.